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#include <fstream>
#include <vector>
using namespace std;
int N;
vector<int> bit(150002,0),v;
ifstream in("aib.in");
ofstream out("aib.out");
void update(int i,int val)
{
while(i<=N)
{
bit[i]+=val;
i+= i & -i;
}
}
int prefixSum(int i)
{
int sum=0;
while(i>0)
{
sum+=bit[i];
i-= i & -i;
}
return sum;
}
int rangeSum(int i, int j)
{
return prefixSum(j) - prefixSum(i-1);
}
int lbound(int ca)
{
int l=1,r=N,mid=-1,aux;
while(l<r)
{
mid=(l+r)/2;
aux=prefixSum(mid);
if(aux>=ca)
r=mid;
else
l=mid+1;
}
return l;
}
int main()
{
int x,m;
in>>N>>m;
v.push_back(0);
for(int i=1;i<=N;i++)
{
in>>x;
v.push_back(x);
update(i,x);
}
int op,a,b;
for(int i=0;i<m;i++)
{
in>>op;
if(op==0)
{
in>>a>>b;
update(a,b);
}
else if(op==1)
{
in>>a>>b;
out<<rangeSum(a,b)<<'\n';
}
else if(op==2)
{
in>>a;
int aux=lbound(a);
if(rangeSum(1,aux)!=a)
out<<-1<<'\n';
else
out<<aux<<'\n';
}
}
return 0;
}